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1.
本文利用所设计的一种新型流动注射液-液萃取重力分相器,建立了流动注射液溶剂萃取原子吸收光谱法测定铅的新方法,详细地研究了流动注射在线萃取的实验条件及流路系统,方法的精密度和检出限分别为2.5%(n=11)和2.8μg/L(k=3)。用拟定的方法测定了峰蛹,粮食等生物样品中的铅,结果与参考值相吻合。  相似文献   

2.
本文采用流动注射在线萃取火焰原子吸收光谱法测定硫酸电解液中微量铅,考察了水相介质,共存离子,萃取装置,相比等因素的影响。分析含铅1.4mg/L和0.16mg/L的试样,分析值的相对标准偏差(n=10)分别为3.9%和12.3%,方法检出限为0.024mg/L。  相似文献   

3.
设计了在线液-液萃取多用重分布相器及相应流动注射流路系统与ICP-AES法联用。具有良好的分析性能,通过对矿石中某些重稀土元素在硝酸介质中被TBP萃取的应用研究表明钇,镱,铒的检出限(3σ)分别为6.8ng/mL,0.2ng/mL和1.5ng/mL,精密度(RSD%)分别为0.24,0.47和1.8,进样频率为25-30个/h。  相似文献   

4.
应用流动注射在线萃取技术将PdCl^2-6萃入2-巯基苯并噻唑-甲基异丁基酮直接进行石墨炉原子吸收测定。研究了流动注射在线萃取-石墨炉原子吸收光谱法测定地质样品中钯的实验条件、流路参数等。采样速率为20样/h,RSD(n=10)为4.8%,测定Pd的特征质量为2.6*10^-11。  相似文献   

5.
设计了在线液-液萃取多用重力分相器及相应流动注射流路系统与ICP-AES法联用,具有良好的分析性能.通过对矿石中某些重稀土元素在硝酸介质中被TBP萃取的应用研究表明钇、镱、铒的检出限(3σ)分别为:6.8ng/mL、0.2ng/mL和1.5ng/mL.精密度(RSD%)分别为0.24、0.47和1.8.进样频率为25~30个/h.  相似文献   

6.
酚的标准测定方法[1]操作繁琐且对环境有污染.基于个氨基安替比琳的流动注射方法(FIA)[2~4]大多要用到氯仿且灵敏度不高,Frenzel等[5]将C18吸附柱引人FIA体系,灵敏度可以大大提高,但不能消除干扰.本文将填充AmberliteXAD-2树脂的固相萃取微柱装人流动注射流路,在线富集痕量酚和分离干扰物,从而快速、灵敏、选择性地测定水中酚类物质.1实验部分1.1仪器与试剂GilsonMiniPuls-2蠕动泵(法国);756-紫外/可见分光光度计(宜兴分析仪器厂),Hellma178.12流动池(18μL,10mm光程),XWY-104记录仪,Rheodyne5041注射阀…  相似文献   

7.
扑热息痛的光化学荧光特性及其分析应用   总被引:3,自引:0,他引:3  
研究了扑热息痛(PR)的在线光化学荧光特性。发现丙酮可提高PR的光化学反应速率并增强其光化学荧光强度;反应介质的PH值(7.7~11.2)对光化学反应的速率影响不大,但对光化学荧光的强度影响明显。以含有0.04%丙酮的PH9.6硼砂硼砂缓冲液作为反应介质,建立了流动注射在线光化学荧光测定扑热息痛的新方法,检测限(3σ)为19μg/L,相对标准偏差为0.6%,分析速度达60次/h。应用本法测定了4种  相似文献   

8.
研究了流动注射在线离子交换预富集及在线氢化物发生法与原子荧光光谱法的联用技术。设计了双柱交替正向富集和反向洗脱的在线离子交换流路系统。在采样频率为30次/h下,灵敏度较常规流动注射氢化物发生原子荧光光谱法提高11倍。应用于环境水样中痕量碲的分析,获得了满意的结果。  相似文献   

9.
流动注射在线共沉淀预富集火焰原子吸收法测定痕量铜   总被引:3,自引:0,他引:3  
研究了以Ni^2+-DDTC为共沉淀载体,流动注射在线共沉淀预富集-火焰原子吸收光谱法测定痕量铜的体系,在0.3mol.L^-1的硝酸介质中,铜离子在编织反应器中与Ni^2+-DDTC(产生共沉淀,并被收集在编织器内壁上,用甲基异丁基酮(MIBK)在线洗脱沉积物并引入火争原子化器中测定。当富集时间为40s时,40μg.L^-1的铜10次测定的相对标准偏差为3.0%,灵敏度提高60倍,检出限(3σ)  相似文献   

10.
非平衡流动流射分光光度法在线测定痕量铅的研究   总被引:14,自引:2,他引:14  
采用流动注射分析技术,研究了碱性介质中铅与meso-四-(4-三甲铵基苯)卟啉高灵敏的显色反应,用自制的微机化流动注射分析仪准确控制反应时间,利用非平衡法原则,优化了实验条件,建立了在线测定痕量铅的新方法。线性范围为0.00-2.00mg/L,分析速度每小时测定120次,方法适用于直接测定煤矿井水、鱼塘水、电场废水和自来水中的铅,所得的结果令人满意。  相似文献   

11.
ICP-AES测定铀污染土壤植物中铀的研究   总被引:2,自引:0,他引:2  
采用电感耦合等离子体发射光谱(ICP-AES)对铀污染土壤植物中铀的测定方法进行了研究.在λU385.958 nm处,选择了仪器的最佳工作条件,考察了酸度和常见共存元素对测定的干扰情况,并且对比了干灰化消解和湿式消解对测定的影响.研究发现2%硝酸溶液为最佳介质,干扰离子对测定没有显著影响,干灰化消解比湿式消解得彻底.在选定条件下,方法检出限为0.18 mg·L-1,测定下限为0.61 mg·L-1,5.0000 mg·L-1的铀标准溶液的相对标准偏差RSD(n=10)为0.81%,方法回收率为96.2%~106.2%.该方法操作简单,快速.结果表明,用ICP-AES测定铀污染土壤植物样品中的铀是可行的.  相似文献   

12.
对血清中Na离子含量的测量不确定度进行评定。不确定度的来源主要包括Na离子标准工作液的配制过程、血清样品的定容消化制备、标准曲线拟合、钠离子各分量不确定度的合成等引入的不确定度计算出各分量的不确定度,通过合成得到测量结果的合成不确定度、扩展不确定度及测试结果的报告形式。  相似文献   

13.
The toxicity of inorganic trivalent arsenic for living organisms is reduced by in vivo methylation of the element. In man, this biotransformation leads to the synthesis of monomethylarsonic (MMA) and dimethylarsinic (DMA) acids, which are efficiently eliminated in urine along with the unchanged form (Asi). In order to document the methylation process in humans, the kinetics of Asi, MMA and DMA elimination were studied in volunteers given a single dose of one of these three arsenicals or repeated doses of Asi. The arsenic methylation efficiency was also assessed in subjects acutely intoxicated with arsenic trioxide (As2O3) and in patients with liver diseases. Several observations in humans can be explained by the properties of the enzymic systems involved in the methylation process which we have characterized in vitro and in vivo in rats as follows: (1) production of Asi metabolites is catalyzed by an enzymic system whose activity is highest in liver cytosol; (2) different enzymic activities, using the same methyl group donor (S-adenosylmethionine), lead to the production of mono- and di-methylated derivatives which are excreted in urine as MMA and DMA; (3) dimethylating activity is highly sensitive to inhibition by excess of inorganic arsenic; (4) reduced glutathione concentration in liver moderates the arsenic methylation process through several mechanisms, e.g. stimulation of the first methylation reaction leading to MMA, facilitation of Asi uptake by hepatocytes, stimulation of the biliary excretion of the element, reduction of pentavalent forms before methylation, and protection of a reducing environment in the cells necessary to maintain the activity of the enzymic systems.  相似文献   

14.
茶叶中新型污染物高氯酸盐在近年来受到越来越多的关注,相应的检测技术也在不断加强.参考国内外文献,综述了茶叶中高氯酸盐的检测方法.目前,茶叶中高氯酸盐的检测方法主要有离子色谱法(IC)、离子色谱-质谱法(IC-MS)和高效液相色谱-串联质谱法(LC-MS-MS).比较了不同检测方法的局限性和优越性,重点比较了高效液相色谱-串联质谱法不同前处理方法、净化小柱和检测条件的优劣,对茶叶高氯酸盐检测技术的发展和研究进行了展望,为检测茶叶中高氯酸盐的新材料研发和检测新标准的建立提供理论依据.  相似文献   

15.
16.
A proficiency testing round was undertaken to assess the performance of laboratories to measure acrylamide in a sample of crispbread. Retail samples of crispbread were ground to a fine powder and after thorough mixing were packed in 40 g units for distribution. Ten samples were selected at random and analyzed in duplicate for acrylamide by liquid chromatography/mass spectrometry (LC/MS). Standard statistical tests showed that the material was homogeneous for the purposes of proficiency testing. Test samples were distributed to 55 laboratories in 16 countries in Europe, North America, Australia, and the Middle East. The results were analyzed by standard proficiency testing statistical procedures, and laboratories were awarded z-scores on the basis of their reported results. Based on a target standard deviation (sigmap value) taken from the Horwitz equation, for a robust mean value of 1.2 mg/kg acrylamide, satisfactory results (z-score within +/- 2 for those between 0.8 and 1.6 mg/kg) were obtained by 86% of the 37 laboratories that returned results. Only 1 laboratory was unsatisfactory and 4 had questionable results. About equal numbers of laboratories used gas chromatography (GC)/MS and LC/MS procedures with about 25% using MS/MS and one using GC with electron capture detection. There was no evident trend in performance or bias in results. GC/MS and LC/MS data were evenly distributed across the population of laboratories reporting results.  相似文献   

17.
超临界流体萃取技术在提取中药挥发油中的应用   总被引:5,自引:0,他引:5  
用超监介CO2流体萃取技术对多种中药挥发油的提取进行了综述,并将其与传统的水蒸馏法进行比较。结果表明,用超临界流体法不仅挥发油的收率高,而且提取时间也大大缩短。  相似文献   

18.
It was shown that the strength characteristics of the samples produced from thermoplastics (low density polyethylene, polyamide 6, Armamid, and polyethylene terephthalate) increase as a result of short vibration treating with a frequency close to that of natural vibrations of the structural elements.  相似文献   

19.
Klaos E  Odinets V 《Talanta》1990,37(5):519-526
The direct atomic-absorption determination of chromium in argillites, without preliminary concentration and separation, has been studied. A map of selective flame zones for determining Cr in argillites has been designed. An express method for determining Cr in Estonian argillites has been suggested.  相似文献   

20.
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